The convenience of on-line electronic shopping has led to its widespread acceptance. To shop on-line, a shopper visits an Internet web site provided by a merchant, browses the goods or services on offer, opens and loads an electronic shopping cart, and places an order. However, a significant number of shoppers, by some estimates more than half, abandon their shopping carts and leave the web site without placing orders.
Abandoned shopping carts are not easily detected. Some shoppers fill their carts slowly; consequently, some carts that appear to be abandoned are instead active, and a hasty decision might mistakenly tag these slowly filled but active carts as abandoned. Nevertheless, abandoned shopping carts should be purged as quickly as possible, as they reduce the capacity and responsiveness of the server that supports the electronic commerce web site. Not only do abandoned shopping carts generally occupy the server's database space and waste processor cycles, they also fill the server's shopping tables and thereby put the server at risk of data overflow.
To reduce this risk, a web server typically executes a garbage collection routine periodically, to purge abandoned shopping carts. Because some shopping carts may be active but slow to fill, the garbage collection routine allows a cart to be inactive for a long time before purging the cart. The purpose of this long window of time is to minimize the likelihood of losing a sale or of inconveniencing a customer. So, in many applications, an abandoned cart may be allowed to persist for three months before it is purged by the garbage collection routine.
For on-line shopping services where demand is highly variable, for example services that sell paraphernalia related to sports events, such a long window of time effectively defeats the purpose of the garbage collection routine. For example, during an Olympic Games there may be a sharp peak in demand for items related to a first event. Shopping carts abandoned during this peak may be quite troublesome, as they occupy database resources that may be needed to service another demand peak that accompanies a second event of the Games. On the one hand, in such situations a long garbage collection window may render the garbage collection routing ineffective, particularly when the second event soon follows the first event. On the other hand, a significant number of shoppers may purposefully allow a shopping cart to persist over the entire course of the Games, accumulating items from day to day, and place an order at a convenient time after the Games. To purge these seemingly abandoned carts would be a mistake that could have significant consequences in terms of lost sales and alienated shoppers.
Thus there is a need for an improved way of purging abandoned shopping carts from electronic commerce web servers, so that the carts may be purged at the earliest possible moment that is consistent with sufficiently minimizing the risk of mistakenly purging shopping carts that are active but slow to fill, and thereby losing sales and inconveniencing shoppers.